Delayed Onset Posttraumatic Stress Disorder: A Systematic Review of the Evidence

Objective: Since its introduction in DSM-III there has been controversy over the prevalence, and even the existence, of delayed-onset posttraumatic stress disorder (DOPTSD). In an attempt to resolve the discrepant findings we conducted a systematic review of the evidence concerning this condition. Method: The literature was searched for case reports and group studies with adequate measurement of DOPTSD according to DSM criteria. Results: Ten case studies and 19 group studies met criteria for inclusion in the review. Studies consistently showed that delayed onset PTSD in the absence of any prior symptoms was extremely rare, whereas delayed onsets that represented exacerbations or reactivations of prior symptoms accounted on average for 38.2% and 15.3% respectively of military and civilian cases of PTSD. Conclusions: The discrepant findings in the literature concerning prevalence can be largely, but not completely, explained as being due to definitional issues. Very little is known at present about what distinguishes the delayed onset and immediate onset forms of the disorder. Continuing scientific study of DOPTSD requires future editions of the DSM to adopt a definition that explicitly accepts the likelihood of at least some prior symptoms